1. Field of the Invention
This invention concerns dumping apparatus for lifting and turning a loaded railroad car or other container, upwardly and to one side until the top of the container faces the ground permitting the contents of the container to spill by gravity onto a dumping area. More particularly, the invention provides appropriate frame means in a railroad car parking area which rigidly engage the railroad car or other container and provides further means for rotating the frame and engaged railroad car or other container as a unit about a generally horizontal axis which is positioned to one side of the frame means. The movement of the frame and railroad car or other container about a single generally horizontal axis is achieved by means of two hydraulic piston motors, each of which is secured to an intermediate support member which is pivotal about the same generally horizontal axis. A first hydraulic piston motor connects the intermediate support member to the frame means. A second hydraulic piston motor connects the intermediate member to support means located between the container parking area and the dumping area.
2 Description of the Prior Art
Numerous devices are known for cradling a railroad car in a frame and elevating the frame and engaged railroad car as a combination upwardly and sidewardly for the purpose of dumping the contents of the railroad car on to a dumping area located beside the railroad tracks on which the railroad car is delivered to the dumping installation. A number of these apparatus employ pulleys or chains (or ropes or cables) to elevate the railroad car and frame and thereafter to move the railroad car into a dumping position. See U.S. Pat. Nos. 556,458, to CLARKSON; 564,646, to RASCH; 665, 025, to LONG; 711,728, to LONG; 720,557, to BROWNING; 1,009,331 to McMYLER; 1,084,437; to HULETT; 1,575,415, to CRIST. Other car dumping apparatus rotates the railroad car frame combination about a single generally horizontal axis. See U.S. Pat. Nos. 1,360,607, to WILLIAMSON et al; 1,478,723, to WRIGHT; 1,585,730, to MITCHELL; 1,590,826, to HULETT; 1,654,919, to CASE; 1,700,693, to BILES; 1,833,309, to SHUTT; 2,054,199, to KALTENBACH. Car dumping apparatus employing gears and large rotatable gear segments is disclosed in U.S. Pat. No. 1,700,693, BILES.
A recent development is a dumping apparatus which employs two hydraulic piston motors for the purpose of turning a railroad car and an engaged frame about two generally horizontal parallel, separate axes. See U.S. Pat. No. 4,134,503, BAKER.
The difficulties of operating railroad apparatus with pulleys and chains (or ropes or cables) or with large gear segments are numerous. There are many advantages for the use of hydraulic piston motors of the type described in the BAKER patent, supra. However the BAKER device utilizes two distinct, spaced-apart horizontal axes and uses two hydraulic piston motors with a two-piece intermediate element. The two-piece intermediate element rotates about one of the two horizontal axes while maintained in a rigid relationship with the frame. Thereafter the second hydraulic piston motor rotates the frame and car assembly about an axis on the two-piece intermediate element. The arrangement creates over-reach whereby at least one of the hydraulic piston motors must be double-acting in order to return the frame and dumping railroad car to the initial position. The thrust of the hydraulic piston motor of the BILES apparatus is directed away from the direction of movement requiring significant excess pressure to advance the hydraulic piston motor.